The present invention relates generally to ablation devices and, more specifically, to an assembly of ablation elements arranged in a staggered configuration.
Hypertension is a major global public health concern. An estimated 30-40% of the adult population in the developed world suffers from this condition. Furthermore, its prevalence is expected to increase, especially in developing countries. Diagnosis and treatment of hypertension remain suboptimal, even in developed countries. Despite the availability of numerous safe and effective pharmacological therapies, including fixed-drug combinations, the percentage of patients achieving adequate blood-pressure control to guideline target values remains low. Much failure of the pharmacological strategy to attain adequate blood-pressure control is attributed to both physician inertia and patient non-compliance and non-adherence to a lifelong pharmacological therapy for a mainly asymptomatic disease. Thus, the development of new approaches for the management of hypertension is a priority. These considerations are especially relevant to patients with so-called resistant hypertension (i.e., those unable to achieve target blood-pressure values despite multiple drug therapies at the highest tolerated dose). Such patients are at high risk of major cardiovascular events.
Renal sympathetic efferent and afferent nerves, which lie within and immediately adjacent to the wall of the renal artery, are crucial for initiation and maintenance of systemic hypertension. Indeed, sympathetic nerve modulation as a therapeutic strategy in hypertension had been considered long before the advent of modern pharmacological therapies. Radical surgical methods for thoracic, abdominal, or pelvic sympathetic denervation had been successful in lowering blood pressure in patients with so-called malignant hypertension. However, these methods were associated with high perioperative morbidity and mortality and long-term complications, including bowel, bladder, and erectile dysfunction, in addition to severe postural hypotension. Renal denervation is the application of a chemical agent, or a surgical procedure, or the application of energy to partially or completely damage renal nerves to partially or completely block the renal nerve activities. Renal denervation reduces or completely block renal sympathetic nerve activity, increases renal blood flow (RBF), and decreases renal plasma norepinephrine (NE) content.
The objective of renal denervation is to neutralize the effect of renal sympathetic system which is involved in arterial hypertension. Device-based renal denervation may achieve such objective, but may produce possible complications of renal artery/vein stenosis. Thus, there is a need for a device that can perform renal denervation with reduced risk of renal artery/vein stenosis.